I guess this is the right thread to post it in: I heard months ago that Discovery season 3 was set to feature a crossover with the Kelvin side of Star Trek.
The crossover was supposed to be Michael Burnham meeting Nimoy Spock (the one that we saw in the Kelvin movies). They planned to have a body do the acting, with their head being CGI'd into Leonard Nimoy's face.
They weren't able to film this scene originally, but I heard Discovery S3 recently had some quick reshoots & additional filming in Vancouver, Canada. Very secretive and stuff. I think they ended up filming this Kelvin crossover scene there.
Also, I think this might be the scene where it happens. I'm not sure.